A bad corrosion graphic?

In recently searching for sacrificial images online, I came upon the following graphic (at opentextbc.ca)...

...and I think it has a pretty significant error in representing the science of how sacrificial protection from corrosion works.

I'll put my reasoning after the jump...

Sacrificial anode photos and links

I was recently searching online for some better images of sacrificial anodes for our material science slideshow at school, and I thought I might as well put these out there for any other science teachers using the blog.

I will say in advance that I didn't take any of these, and that's why I'll be linking to the source. All were accessed in January and February of 2020. The links may rot, but I'll keep the images up.

What is an anode rod & how does it work?

I know the answer.

Do you?

If you don't, you might want to check out Landmark Home Warranty's great webpage explaining the usefulness of and science behind hot water heater anode rods.

There's even an infographic in case you don't like so many words.